Leather-working machine.



A. H. KEHRHAHN.

LEATHER WORKING MACHINE. APPLIoATIoN FILED MAY 3.1910.

Patented Jan. 17, 1911.

2 SHEETS-SHEET 1.

nu: Noums PETERS cu', wAsmNcraN. n, c4

A. H. KEHRHAHN.

LEATHER WORKING MACHINE.

APPLIoATIoN FILED MAY a, 1910.

Patented Jan. 17,1911.

2 SHEETS-SHEET 2.

Fig. z- 4 FEE@ LEATHER-WORKING MACHINE.

To all whom it may concern:

Be it known that l, ALEXANDER H. KEHR- HAHN, a subject of the King ofPrussia and Emperor of Germany, residing at Ottostrasse 13,Frankfort-on-the-Main, Prussia, Germany, have invented certain new anduseful Improvements in Leather-Working Machines, of which the followingis a specication.

This invention relates to machines for operating upon hides, skins, andleather, such as those employed by tanners or curriers for fieshing,scudding, unhairing, shaving, ironing, glazing, or for operating uponthe work in any manner by tools such as revolving bladed cylinders,rollers, glasses, or heated irons.

The invention consists in friction driven mechanism and manuallyoperative means for controlling the friction mechanism, in combinationwith relatively movable coacting members for operating upon the workwith pressure.

The purpose of the invention is to provide power driven mechanism forAeffecting relative movement and pressure of the coacting work-engagingmembers, whereby the relative movement, controlled by the manuallyoperative means, may be begun, continued, interrupted, resumed, orreversed, and whereby the pressure of said members may be begun,continued, increased, decreased, or relieved, at any time, and for anylength of time, at the will of the operator.

For purposes of illustration the invention in the embodiment shown bythe accompanying drawings is combined with a shaving machine whichincludes a bladed cylinder. The machine also includes a bed roll whichis movable bodily toward and from the bladed cylinder, and which isadapted to press the work with more or less pressure against thecylinder. The bed roll is capable of sufficient movement to facilitatethe insertion of the work, and the present invent-ion is embodied inmechanism for causing the bed roll and bladed cylinder to coact upon thework with variable pressure.

For the purposes mentioned the invention includes friction drivingmechanism under the control of the operator for exerting variabletension tending to move one of said coacting members toward the other.Motive power for causing such movement is not derived from the operator,but may be derived from any appropriate source of power suchSpecification of Letters Patent.

Application filed May 3, 1910.

Patented Jan. 17, 1911.

serial No. 559,090.

as a pulley. The friction element included in the actuating mechanismmay be controlled by the operator so that the movable member whichengages the work may be caused to coact with more or less pressure withthe complemental member. 1n the form illustrated the controlling meansconsists of a treadle, and it is so related to the friction mechanismthat an increase of pressure upon the treadle effects an increase offriction, and consequently al relatively great increase of pressure ofthe work-engaging members upon the work.

One advantage afforded by the invention is that any desired length ofmovement of the bed roll may be had without requiring an appreciablemovement of the treadle. Another advantage is that a relatively greatpressure of the work-engaging members may be effected by a relativelyslight pressure upon the treadle. So long as the .pressure upon thetreadle is suiiicient the pressure of the work-engaging members iscontinuous, but the pressure of the work-engaging members may be variedby a slight variation of pressure upon the treadle. The work-engagingmembers in the form illustrated are arranged so that they may becomeseparated solely by reason of gravity when the pressure upon the treadleceases, but this is not essential.

Of the accompanying drawings forming a part of this specification,Figure 1 represents a side elevation of a shaving machine embodying oneform of the present invention. F ig. 2 represents a front elevationthereof.

The same reference characters indicate the same parts wherever theyoccur.

On the drawings a machine base is indicated at 10 and two members of thesupporting frame are indicated at 11 and 1Q. lThe frame members areprovided with stationary bearings for a shaft 13, which carries a toolsuch as a bladed cylinder 14e. A bed roll is indicated at 15 and ismounted so as to be movable toward and from the cylinder 14. The bedroll is mounted upon a shaft 16, whose ends are mounted in bearings 17in an oscillatory frame 18. The frame 18 is mounted upon a shaft orpivots 19, supported by the frame members 1l and 12. So far as thepresent invention is concerned it is immaterial whether the bed rollmoves toward and from the bladed cylinder, or whether the bladedcylinder moves toward and from the bed roll, or whether the bed roll andcylinder both have movement toward and from each other.

The normal position of the movable frame 18 is shown by dotted lines inFig. 1. lhen the frame is in this position the bed roll 15 is relativelydistant from the cylinder 14 and ample space is thus provided forinsertion of the work. After the work has been in-` serted between thebed roll and the bladed cylinder the bed roll is moved toward thecylinder so as to press the work against the blades of the cylinderwhich is continuously rotated to cause the blades to act upon the work.Rotation may be imparted to the cylinder by a belt 20 and pulley 21ailixed upon shaft 13 of the cylinder.

The mechanism thus far described is not new, and does not form any partof the present invention, but the invention is embodied in the meanslhereinafter described for moving the bed roll toward the cylinder.

The frame 18 which supports the bed roll is provided with gear segments22 and 23 respectively. These segments are intermeshed with pinions 24'aflixed upon a shaft 25. The shaft is mounted in ixed bearings in theframe members 11 and 12 and is provided with a pulley 26. An endlessbelt 27 passes over the pulley 2G and also over a driving pulley 28 andidle pulleys 29 and 30. The driving pulley 28 is aiiixed upon a shaft 31mounted in fixed bearings in the frame inembers 11 and 12. The pulley 29is carried at the free ends of an arm 32, pivoted at 38, and maybeadjusted to compensate for variation in the length of the belt 27. Forthis reason the frame member 11 is provided with bosses 84tin whichoppositely disposed adjusting screws 35 and 36 are threaded. Theadjusting screws are arranged to engage the free end of the arm 32 andto lock said arm positively in the desired position. The pulley 30 ismounted at the free end of an arm 37 keyed er otherwise affixed upon arock-shaft 38. The arm 37 is connected to a spring 39 which exerts itstension tending to relax the tension of the belt 27. A lever l0 isatlixed to the shaft 88 and is provided with a treadle 11.

lThe upward movement of the arm 37 due to the tension of the spring 39may be limited by an adjust-able stop e2 attached to the frame member11. rEhe gear segment 22 is here shown as being adjustable with relationto its movable frame 18'7 the object being to cause the pinions 211 toact equally upon the segments 22 and 23. For this purpose the segment 22is provided with concentric slots 22, and the frame18 is provided withclamping studs 43 which extend through the slots 22. The segment 22 isfurther provided with ears e4 (see Fig. 2) in which are threaded a pairof oppositely disposed adjust-ing screws 45, said screws abuttingagainst surta-cese@ of the frame 18 to'position the segment rigidly withrelation to said frame.

The machine thus constructed may be operated in the following manner:After the introduction of the work between the bed roll 15 and thebladed cylinder 14: the bed roll may be moved toward the cylinder bydepressing the treadle 41. 1t is proposed to cause the driving pulley 28to be rotated continuously and to thereby keep the belt 27 constantly inmot-ion in the direction indicated by the arrow in Fig. 1. Because ofthe initially relaxed condition of the belt it may slip over the pulley26 without driving the latter. 1t will be observed that the belt engagesapproximately 180O of the rim of the pulley 26 and that it engagesconsiderably more than 180o of the rim of the pulley 28. A slightpressure upon the treadle is suiiicient to remove the slack from thebelt 27 and cause the belt to exert the requisite friction upon thepulley 26. The pulley 26 lmay thus be rotated to elevate the bed roll15, the .speed of elevation depending upon the degree of pressure uponthe treadle. .Vhen the work upon the bed roll is moved into engagementwith the cylinder 14 the movement of the bed roll is, of course,arrested but the pressure of the bed roll in the direction of thecylinder continues so long as tension is applied tothe belt 27 bydownward pressure upon the treadle. The workengaging members are thussupported in cooperative relation through the medium of a continuouslymoving belt 27 which continues to slip upon the pulley 26. 1t is obviousthat the pressure of the work-engaging members may be increased ordecreased while they rcmain in cooperative position by varying thedownward pressure upon the trea'dle. The maximum pressure of thework-engaging members may be determined by various means, such as a stopscrew 4:7 threaded in the treadle lever 40. As here shown the stop 1:7is arranged to engage the base 10 and thus limitvthe downward movementof the treadle. The screw 47 may be adjusted to permit more or lessmovement of the lever 410 and to thereby increase or decrease themaximum tension of the work-engaging members. Upon the completion of anoperation the movable frame 18 may be permitted to descend by gravity bvrelieving the downward pressure upon the treadle.

It is obvious that the belt and pulley 26 constitute coacting frictionmembers of one form of friction clutch inasmuch as they may be caused toslip or to coperate with any desired degree of friction. 1n order toinsure a greater degree of friction of the belt with the pulley 28 thanwith the pulley 26 so that the slipping of the belt will be confined tothe pulley 26 the rim of the pulley 28 may be covered with frictionmaterial 4S such as leather. Any tendency of thei belt to slip laterallyupon the pulley 2G may be overcome by providing guides (not shown) uponthe frame member 11, or by providing fianges (not shown) at the sideedges of the pulley.

An advantage of a belt and pulley as a friction clutch, as distinguishedfrom what are termed cone clutches and expanding clutches is that thefriction surface of the belt has suflicient opportunity to cool whilepassing from one pulley to another. Another advantage is that thefriction surface of the belt may be coated with some liquid frictionproducing substance, the belt being readily accessible for this purpose.Adhesion of the belt with relation to the pulley 26 may thus beincreased. A third advantage is precision of tension due to theelasticity of the belt. The pulleys 29 and 30 are movable in directionsubstantially parallel to the tangent portions of the belt, andtherefore a movement of either of said pulleys eects a shortening of thebelt commensurate to twice the distance through which the pulleys aremoved. Thus a relatively short adjustment of the pulley 29, or arelatively short movement of the treadle effects a relatively greatshortening of the belt. It is apparent, however, that a cone clutch, eX-panding clutch, or any other form of friction clutch may be employed toeffect the desired result, and for this reason the term friction clutchis intended to include the various forms in which a friction clutch maybe embodied.

The arrangement of the pinions 2i and segments 22 is such as to maintainthe leverage of the closing force at an equal ratio, as distinguishedfrom other construction and arrangement often employed for this purpose.The meaning of the foregoing statement may better be understood when itis considered that the mechanism now in use for operating machines ofthis type includes a crank and a connecting rod for transmittingmovement to close the work-engaging members. One result of a crank andconnecting rod is a constantly changing ratio of leverage, and it iscustomary to arrange the crank so as to pass over what is sometimestermed the dead center when the work-engaging members are closed. Whenthe crank is so arranged, the ratio of leverage is at maximum when thework-engaging members are closed, and, consequently, a relatively slightdegree of power is sufficient to movethe crank over the dead center. Theillustrated arrangement of gears, or any equivalent arrangement by whichthe leverage of the closing force is maintained at an equal ratio,ispreferred because the closing tension of the work-engaging members maybe better controlled through the medium of the mechanism provided forthat purpose.

Having thus explained the nature of my said invention and described away of constructing and using the same, although without attempting toset forth all of the forms in which it may be made or all of the modesof its use, what i claim is l. A machine of the character described,comprising a working tool and work support, one movable toward and fromthe other, a continuously moving member, means having frictionalengagement with said continuously moving member for closing saidwork-engaging members, and independently controllable means foreffecting and varying the frictional tension of said continuously movingmember on said means.

2. A machine of the character described, comprising two coactivework-engaging members, one of said members being movable toward and fromthe other, a continuously moving endless belt, means having frictionalengagement with said belt for closing said work-engaging members and formaintaining closing tension thereof, and manually operative means forvarying the tension of said belt to vary the closing tension of saidwork-engaging members.

3. A machine of the character described, comprising two coactivework-engaging members, one of said members being movable toward and fromthe other, a continuously moving member, means having frictionalengagement with said continuously moving member for closing saidwork-engaging members, and for maintaining closing tension thereof, andmeans including a treadle for varying the frictional tension of saidcontinuously moving member, said treadle means'being adapted to effect arelatively great increase of frictional tension by a relatively slightincrease of pressure upon the treadle.

4. A machine of the character described, comprising two coactivework-engaging members, one of said members being movable toward and fromthe other, a continuously moving member, means having frictionalengagement with said continuously moving member for closing saidwork-engaging members, and for maintaining closing tension thereof,means including a treadle for varying the frictional tension of saidcontinuously moving member, and a stop for limiting the movement of saidtreadle means.

5. A machine of the character described, comprising two coactivework-engaging members, one of said members being movable toward and fromthe other, a continuously moving endless belt, means having frictionalengagement with said belt for closing said work-engaging members,movable means engaging said belt for varying the frictional tensionthereof with said closing means, and means engaging said belt foradjusting the length of the belt with relation to said closing means andsaid tension-varying means.

6. A machine of the character described, comprising two coactivework-engaging members, one of said members being movable tow'ard andfrom the other, a continuously moving endless belt, means havingfrictional engagementwith said belt for closing said work-engagingmembers, a treadle, and means actuated by said treadle and engaging saidbelt for Varying the frictional tension of said belt with said closingmeans said treadle actuated means being arranged to effect a shorteningof the belt commensurate to twice the length of movement. of the saidtreadle actuated means.

7. A machine of the character described, comprising two coactivework-engaging members, one of said members being movable toward and fromthe other, an endless belt, means having frictional engagement with saidbelt for closing said work-engaging members and for maintaining closingtension thereof, and a continuously rotating pulley for drivingsaidbelt., said pulley having a belt engagingv surface composed offriction material adapted to eifect continuous driving of the belt.

8. A machine of the character described,

comprising two coactive work-engaging members, one of said members beingmovable toward and from thesother, a continuously moving member, arotatable member having frictional engagement with said continuouslymoving member and gears connected w'ith said rotatable member forimparting movement to close said work-engaging members, said gears beingarranged to be arrested by the .work-engaging members when closed.

9. A machine of the character described, comprising two coactivework-engaging members, one of said members being movable toward and fromthe other, a continuously moving member, a rotatable member havingfrictional engagement with said continuously moving member, and gearsconnected with said rotatable member for imparting movement to closesaid work-engaging members, said gears being connected with one of saidwork-engaging members so as to maintain the leverage of the closing'force at an equal ratio.

In testimony whereof I have affixed my signature, in presence of tw'owitnesses.

ALEXANDER H. KEHRHAHN.

Witnesses:

W. P. ABELL, P. l/V. PEZZETTI.

